1. Field of the Invention
This invention relates to improvements in off-highway vehicles and more particularly, but not by way of limitation, to a bottom dump type off-highway vehicle of the general two axle type having a single-wheel in all positions, and having a front engine in combination with a rear wheel drive.
2. Description of the Prior Art
Off-highway vehicles are in widespread use today for hauling extremely large and heavy loads in order to reduce time and expense in many industries, such as in the opening mining industry, large construction industry, and the like. The usual or conventional off-highway vehicle of this type is a tractor-trailer hauling unit such as shown in the Lackey et al U.S. Pat. No. 3,134,628, issued May 26, 1964, and entitled "Tilting Dumping Trailer". These units are usually powered only on the middle axle, and if proper tire loading is maintained for a balanced design, there is not adequate loading on the drive axle for negotiating roadway grades. Tractor-Trailers are thus normally limited to grades of not more than three percent or four percent maximum. In addition, tractor-trailer type hauling vehicles usually have only three points of support and as a result may turn over somewhat readily. The relatively high center of gravity of these units also increases the instability thereof. Of course, as usage of these vehicles increases, there is an ever increasing demand for even larger and heavier units, which adds to the difficulties encountered in both the manufacture and use of the vehicles.